Keyboard



FIG. 1 is a top, front and right side perspective view of a keyboard showing my new design;

FIG. 2 is a rear and left side perspective view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and

FIG. 6 is a right side elevational view thereof. 

The ornamental design for a keyboard, as shown and described. 